Iranica Journal of Energy and Environment (IJEE)

243-254

Authors: M. S. Okundamiya, J. O. Emagbetere, E. A. Ogujor

This paper examines the viability of a grid-connected hybrid energy system (HES) for domestic electricity generation in the developing world. It aims to determine the techno-economic benefits of operating a wind energy conversion system. The HES consists of the grid power supply, wind energy conversion, power electronics, and storage units. The grid supply unit incorporates a probability- based prediction technique. The wind energy system modelling is based on the piecewise third order polynomial, using wind turbine power profile supplied by the manufacturer. The formulated optimization problem was solved using a hybrid Genetic Algorithm and Pattern Search (h-GAPS) technique. The h-GAPS based approach constrains the generation and distribution of power to ensure efficient operation. Analysis performed for a typical residential area used meteorological data for six sites, which spread across Nigeria. Results showed that the proposed power system could bring benefits of cost saving and improve power reliability, but the range of financial benefits depends on the geographical coordinates. In particular, 10kW/5.40kWh capacity wind/battery system installed in Sokoto can deal with 95.4% of the total electricity demand, save more than 77% of electricity payments and increase the reliability by approximately 140%.

260-268

Authors: S. Bentahar, A. Lacherai, A. Dbik, N. El messaoudi, M. El khomri

This study reports the adsorption of crystal violet (CV) cationic dye on natural clay originated from Agadir region (south Morocco) through batch adsorption experiment, in order to develop a low-cost, natural, eco-friendly and alternative adsorbent for the removal of organic pollutants. Several analytical techniques (XRD, BET, TDA, TGA and FTIR) were used to characterize the studied material. The effect of different parameters were studied such as pH (3–10), adsorbent mass (0.02- 0.3 g), contact time (20–120 min), initial dye concentration (100–900 mg/L), and temperature (25– 65 °C) on the adsorption of CV dye. The results Showed That CV adsorption on the natural clay depends on pH, initial dye concentration and temperature. The adsorption equilibrium data were fitted in Langmuir, Freundlich and Timken adsorption isotherm models. The adsorption data obtained were well described by Langmuir isotherm model with correlation coefficients (R2 =0.99). Maximum adsorption capacity of clay was found to be 250 mg/g. Adsorption kinetics were well fitted by Pseudo-second order kinetic model (R2 = 0.999). Thermodynamic study revealed that the adsorption of CV on clay is spontaneous physical sorption process, endothermic and favorable. Experimental results indicate that the clay studied is a promising adsorbent for the removal of cationic dye molecules from aqueous solutions.

274-281

Authors: Marzieh Hamidzadeh, Aliakbar Tarlani, Mitra Ghassemzadeh

In this paper new promoted Fe-NaY catalysts were prepared for ammonia selective catalytic reduction of NO. The prepared catalysts were characterized using X-ray diffraction (XRD), N2 adsorption-desorption, Furrier transform infrared (FTIR) and UV–Vis diffuse reflectance spectra (UV–Vis DRS) techniques. The catalytic results revealed that among the investigated promoters (Li, Na, K, Cs, Mg, Ca, Sr, Ba, Sm, La and Ce), the K, Ba and Ca promoted Fe/NaY catalyst showed higher activity. The apparent activation energies for these catalysts are close together and change in a limited range (14.3 kJ/mol for Mg/Fe/NaY to 38 kJ/mol for Ca/Fe/NaY) because main metal ion (Fe) is fixed in all of these catalysts. The results revealed that decreasing in band gap energy in absorption edge and increasing in total acidity in the Ca/Fe/NaY, Ba/Fe/NaY and K/Fe/NaY improve the catalyst performance. In presence cerium and samarium metal ions band gap energy increased. The NO conversion on the Na/Fe/NaY, Ca/Fe/NaY and K/Fe/NaY catalysts is more than 80%.

290-300

Authors: I. Osasona, A. O. Adebayo, A. E. Okoronkwo, O. O. Ajayi

In this work, the feasibility of batch studies using hydrochloric acid modified cow hoofs (HCH), citric acid modified cow hoofs (CACH) and sodium hydroxide modified cow hoofs (SCH) for removing Cr (VI) from aqueous solution were investigated. Equilibrium data at four different temperatures (25, 35, 45 and 550 C), by contacting Cr (VI) solution at different concentrations with CACH, HCH and SCH were also conducted. The results of this study showed that SCH recorded higher percentage Cr (VI) removal than both HCH and CACH. The pH of 2 was required for maximum removal of Cr (VI) by the three biosorbents. The data obtained for both CACH and SCH were best fitted by Langmuir model while the data obtained for HCH were best fitted by Freundlich model. Thermodynamic parameters for the removal of Cr (VI) revealed the process to be spontaneous and exothermic for HCH and SCH but endothermic for CACH. Therefore, the removal of Cr (VI) from wastewater using these low-cost biosorbents (particularly HCH and SCH) would be economically feasible.

308-315

Authors: N. El Badaoui, Y. Amar, C. Joaqum-Justo, B. Djahed, H. Ammar, R. Benosman, J.-P. Thomé

This study was carried out to investigate the degree, the nature and the origin of pollution in Sidi M’hamed Benali Lake using the physicochemical parameters, saprobic index and cladocerans. For this purpose, water and zooplankton sampling was collected from six sites in lake during five seasons. The average seasonal values of physicochemical parameters showed that the lake undergoes a slight anthropogenic and natural pollution in the dry and wet periods. Presence of certain toxic substances (CN- , Cr, Ni) require us to be more careful in irrigation, bathe and the consumption of fishes of that reservoir. Overall, oligo-mesosaprobic to beta-mesosaprobic rotifers have been prevailing in all five seasons indicating that the water was slightly or moderate polluted. The presence of Bosmina longirostris, Daphnia longispina, Daphnia cuculata, Daphnia ambiga and Sididae diaphonosoma brachyrum indicate bacterial contamination with the intense development of the phytoplankton in the lake, especially in springs and summer. Pearson correlation analysis revealed significant correlation between all of the physicochemical parameters. However, it revealed no significant correlation between zooplanktons occurrence and the majority environmental variables values. In present investigation, the Lake water is relatively little exposed to pollution and does not undergo strong organic pollution.

323-327

Authors: S. A. Amin, S. M. H. Hamdy

The aim of present work was to assess the impact of diesel power generators wastes on radon levels using solid state nuclear track detector CR-39. Forty eight soil samples were collected from area around four power generators located in Al-Ghazalia region in Baghdad, Iraq. Twelve samples at depths of 10-30cm around each generator were taken, three in each direction (N, S, E and W) at different distances (0, 5, and 10m). The value of radon concentrations ranged from 358.3Bq.m-3 at distance 5.0m from G2N to 1258.6Bq.m-3 at distance 10.0m for G2S. The mean values of radon concentrations varied from the lowest value of 604.6 Bq.m-3 to the highest value of 694.7Bq.m-3 in the soil samples around G1 and G4, respectively. The mean value was 636.6 Bq.m-3 . The values of radon level are higher than the international recommended value. Surface and mass exhalation rates were also calculated with average values of (0.35) Bq.m-2 .h-1 and (0.15) Bq.kg-1 .h-1 , respectively. These values are found to be below the limit of the recommended values.

334-339

Authors: N. Sharma, M. P. Rai

Media requirement for microalgae cultivation adds most to the cost of biodiesel production at commercial scale. The present work aims to study the growth of green algae Chlorella pyrenoidosa under fogg`s medium and modified fogg`s medium by replacing KNO3 with urea at different concentrations 0.15, 0.20 and 0.25% (w/v). To reduce the cost of urea, cow urine (CU) was utilized to grow the Chlorella sp. in different volume fractions as 5, 7.5, 10, and 12.5 % (v/v). Biomass production in 7.5% cow urine was achieved 1.93 g l -1 that is almost double in comparison to normal Fogg’s medium (0.82 g l -1 ). Cellular biochemical components such as lipid, protein and carbohydrate are determined quantitatively. The lipid content is found to be 32.7 % in 10 % of cow urine and 22.7 % in 7.5 % cow urine that is much higher than the Chlorella sp. grown under Fogg`s media (7%). The protein content is enhanced to 50.17% and carbohydrate reduced by half in comparison to normal fogg’s medium cells. The extracted lipid is converted into fatty acid methyl esters (FAME) and characterized by GC-MS. The FAME produced from cow urine grown cells showed suitable composition to prove its application as biofuel.